Sensory stimulation evokes in the central nervous system a complex series of neural events. With appropriate averaging techniques thes events can be recorded from the human scalp and are called the Averaged Evoked Potential (AEP). The goal of this research is to develop AEP analysis in the evaluation of central nervoussystem disorders involving sensory dysfunction, and to further understand the neural basis of human sensory experience. Our strategy is to conduct, whenever possible, parallel studies in man and animals. Experiments are proposed in five related areas: 1. Collection of normative data. Such data are necessary for proper interpretation of "abnormal" responses from patients. 2. Neural origins and mediating pathways of AEPs. Here the objective is to clarify the stuctures and pathways within the brain which generate various AEP components; such knowledge is fundamental both to basic and clinical studies. 3. AEP correlates of sensory dysfunction following stroke. Studies during the acute and recovery phases of stroke will assess the usefulness of AEP anaaysis in diagnosis and prognosis. A primate model for AEP-stroke studies will be developed. 4. Epilepsy studies. These continue our investigation of AEP correlates of epilepsy with the goal of assessing the efficacy of anticonvulsant mediaction and determining AEP alterations in different types of epilepsy. An EEG conditioning procedure for reduction of seizures will also be explored. 5. AEP correlates of sensory and perceptuaa processing. These studies are a mixture of basic and appled studies, but have in common the correlation of the AEP with processing of sensory information, including synthetic speech sounds, distorted visual input occuring in amblyopia, in perceptuaa masking, and in auditory dysfunction.